Simulated flights can end 5G signals dispute around airports, says COAI

To break the impasse over installing 5G radios in the 3.3-3.6 GHz band, also called the C band, near airports, the Cellular Operators Association of India (COAI) has told the government there should be controlled flight simulations to prove 5G signals do not interfere in controlling air-borne planes.

“We have said our guard band is large. Our harmonics are unlikely to interfere. But if they don’t believe us, then they should do a simulation in a lab, on a testbed,” COAI Director General S P Kochhar told Business Standard.

In December last year, the Department of Telecommunications (DoT), following recommendations by the Ministry of Civil Aviation, asked telecom operators to avoid deploying 5G base stations around India’s 137 airports.

 

The resultant dispute on this between telecom service providers and airlines has not been resolved.

The COAI, which has all three private telecom service providers Reliance Jio, Bharti Airtel, and Vodafone Idea as its members, has told the government a vast majority of the countries with 5G deployment had not adopted any precautionary measures. More than 20 countries in Europe have deployed the C band at power levels similar to the United States for up to three years, without any harmful interference, it has said.

“In India, C band spectrum has been auctioned in the 3300-3670 GHz band for 5G operations, while altimeters operate in the 4200-4400 MHz band, which is significantly far away,” the industry body said.

In the US, operators have used the 3.7-3.98 GHz frequencies, which are closer to the radio altimeter frequencies inside the aircraft.

The prescribed buffer zone of 2,100 metres around airports will affect 5G availability not only near airports but also airstrips and helipads, many of which are dotted around prime locations in major cities like Delhi, Mumbai, Hyderabad, Chennai, and Kolkata, the COAI told.

In January last year, the Federation of Indian Pilots had sent a letter raising the issue of possible interference of 5G signals in instruments such as radio altimeters in commercial aircraft. The Directorate General of Civil Aviation (DGCA) had also written to the DoT, saying altimeters picked up the faintest of signals from the ground and necessary precautions needed to be taken.

Earlier this year, the International Air Transport Association had also flagged the issue, pointing out that some governments had opted for testing to establish sufficient spectrum separation remained between 5G C band deployments and 4.2-4.4 GHz frequency band used by existing radio altimeters.

It has suggested national air authorities clearly codify and enforce the maximum power limit for 5G C band transmission and ensure a downward tilting of 5G antennas situated particularly in the vicinity of flight paths. It wanted sufficient 5G C band prohibition and precautionary zones around airports be established.